Chickenpox can be detected by a blood test, but the test is called chickenpox-specific antibodies, IgM antibodies, which only become positive when chickenpox is evident, and are likely to be negative until then. This test is not available in most hospital laboratories and is only performed in laboratories with high capacity. Therefore, the clinical diagnosis of chickenpox is not confirmed by blood sampling, but only by the characteristic rash manifestations of chickenpox. If the chickenpox blood test is popularized, it can be used as an auxiliary means to confirm the diagnosis from the laboratory aspect, but from other aspects, its significance is not too great.